Among dihydroflavones, Naringenin, hesperetin, and liquiritin apioside (LA) also exhibited positive effects on COPD, among which hesperetin could not only effectively alleviate inflammation and oxidative stress responses in CES-induced COPD mice by virtue of NAD-dependent protein deacetylase sirtuin-1(SIRT1)/PGC-1α/NF-κB signaling axis (Wang et al., 2020), but also suppress the protein expression of AKT1, IL6, VEGFA, and MMP9 and up-regulate TP53 to reduce the risk of COPD progressing to lung cancer (Zhou et al., 2021). Here, MMP9 is linked to chronic obstructive pulmonary disease.